Semiconductor light-emitting device

• US 6,639,926 B1
• Filed: 03/24/1999
• Issued: 10/28/2003
• Est. Priority Date: 03/25/1998
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Chemical Corporation (Mitsubishi Chemical Group Corp.)
• Original Assignee: Mitsubishi Chemical Corporation (Mitsubishi Chemical Group Corp.)
• Inventors: Goto, Hideki, Nagao, Satoru, Fujii, Katsushi, Shimoyama, Kenji
• Primary Examiner(s): LEUNG, QUYEN PHAN
• Application Number:
  US09/274,767
• Time in Patent Office: 1,679 Days
• Field of Search: 372/45, 372/46
• US Class Current: 372/46.01
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 5/0658 Self-pulsating
• CPC Class Codes: H01S 5/2231 with inner confining structure only between the active layer and the upper electrode
• CPC Class Codes: H01S 5/2272 grown by a mask induced selective growth
• CPC Class Codes: H01S 5/3202 grown on specifically orientated substrates, or using orientation dependent growth
• CPC Class Codes: H01S 5/3206 ordering or disordering the natural superlattice in ternary or quaternary materials
• CPC Class Codes: H01S 5/34326 with a well layer based on InGa(Al)P, e.g. red laser

Abstract

A semiconductor light-emitting device comprising a substrate having a surface having an off-angle to a crystallographic plane of low-degree surface orientation, the substrate having thereon: compound semiconductor layers including an active layer; a selective growth protective film formed on the compound semiconductor layers and having an opening at the region corresponding to a stripe region to which a current is injected; and a ridge-shaped compound semiconductor layer formed to cover the opening. This semiconductor light-emitting device with stable laser property can be manufactured in a simplified way.

Claims

1. A semiconductor light-emitting device comprising a substrate having a surface having an off-angle of 0.5°

to 30°

to a crystallographic plane of (100) or (111), the substrate having thereon;

compound semiconductor layers including an active layer, formed on said surface having said off-angle;

a selective growth protective film formed on the compound semiconductor layers and having an opening at the region corresponding to a stripe region to which a current is injected;

a ridge-shaped compound semiconductor layer formed to cover the opening; and

a compound semiconductor contact layer formed to cover the entire surface of a top portion and side surfaces of the ridge-shaped compound semiconductor layer.

3. The semiconductor light-emitting device according to claim 1 or claim 2, wherein the compound semiconductor layers including an active layer further include a first conductivity type cladding layer and a second conductivity type first cladding layer.

4. The semiconductor light-emitting device according to claim 1 or claim 2, wherein the ridge-shaped compound semiconductor layer includes a second conductivity type second cladding layer.

5. The semiconductor light-emitting device according to claim 1 or claim 2, wherein no protective film is formed either on a top portion or side surfaces of the ridge-shaped compound semiconductor layer.

6. The semiconductor light-emitting device according to claim 1 or claim 2, wherein the substrate has a surface having an off-angle to a crystallographic plane of (100).

7. The semiconductor light-emitting device according to claim 1 or claim 2, wherein the off-angle is 30 degrees or less.

8. The semiconductor light-emitting device according to claim 1 or claim 2, wherein a direction of the off-angle is a direction at an angle of −

30 to 30°

from a direction perpendicular to a longitudinal direction of the stripe region.

9. The semiconductor light-emitting device according to claim 8, wherein a longitudinal direction of the stripe region is a direction at an angle of −

30 to 30°

, and the off-angle direction is a direction at an angle of −

30 to 30°

from a [0-11] direction.

10. The semiconductor light-emitting device according to claim 1 or claim 2, wherein the active layer is an AlGaInP layer or a GaInP layer and the device has an emission wavelength of 630 nm to 690 nm.

2. A semiconductor light-emitting device comprising a substrate having a surface having an off-angle of 0.5°

to 30°

to a crystallographic plane of (100) or (111), the substrate having thereon;

compound semiconductor layers including an active layer, formed on said surface having said off-angle;

a protective film formed on the compound semiconductor layers and having an opening at the region corresponding to a stripe region to which a current is injected;

a ridge-shaped compound semiconductor layer formed to cover the opening, wherein a side wall of the ridge-shaped compound semiconductor layer has a forward mesa shape; and

a compound semiconductor contact layer formed to cover the entire surface of a top portion and side surfaces of the ridge-shaped compound semiconductor layer.

11. A semiconductor light-emitting device comprising

a substrate;

compound semiconductor layers including an active layer formed on the substrate;

selective growth protective film formed on the compound semiconductor layers and having an opening at the region corresponding to a stripe region to which a current is injected; and

a ridge-shaped compound semiconductor layer formed to cover the opening wherein the ridge is horizontally asymmetric.

13. The semiconductor light-emitting device according to claim 11 or claim 12, which further comprising a contact layer formed to cover the entire surface of a top portion and side surfaces of the ridge-shaped compound semiconductor layer.

14. The semiconductor light-emitting device according to claim 11 or claim 12, wherein the ridge-shaped compound semiconductor layer covers a portion of a top surface of the protective film.

15. The semiconductor light-emitting device according to claim 11 or claim 12, wherein the substrate has an off-angle and the direction of the off-angle is a direction at an angle of −

30°

to 30°

from the direction perpendicular to a longitudinal direction of the stripe region.

12. A semiconductor light-emitting device comprising

a substrate;

compound semiconductor layers including an active layer formed on the substrate;

a protective film formed on the compound semiconductor layers and having an opening at the region corresponding to a s tripe region to which a current is injected; and

a ridge-shaped compound semiconductor layer formed to cover the opening wherein a side wall of the ridge-shaped compound semiconductor layer has a forward mesa shape and the ridge is horizontally asymmetric.

16. A semiconductor light-emitting device comprising a substrate having a surface having an off-angle of 0.5°

to 30°

to a crystallographic plane of (100) or (111), the substrate having thereon;

compound semiconductor layers including an active layer, formed on said surface having said off-angle;

a selective growth protective film formed on the compound semiconductor layers and having an opening at the region corresponding to a stripe region to which a current is injected; and

a ridge-shaped compound semiconductor layer formed to cover the opening and a portion of a top surface of the protective film.

18. The semiconductor light-emitting device according to claim 16 or claim 17, wherein the compound semiconductor layers including an active layer further include a first conductivity type cladding layer and a second conductivity type first cladding layer.

19. The semiconductor light-emitting device according to claim 16 or claim 17, wherein the ridge-shaped compound semiconductor layer includes a second conductivity type second cladding layer.

20. The semiconductor light-emitting device according to claim 16 or claim 17, wherein no protective film is formed either on a top portion or side surfaces of the ridge-shaped compound semiconductor layer.

21. The semiconductor light-emitting device according to claim 16 or claim 17, which further comprising a contact layer formed to cover the entire surface of a top portion and side surfaces of the ridge-shaped compound semiconductor layer.

22. The semiconductor light-emitting device according to claim 16 or claim 17, wherein the substrate has a surface having an off-angle to a crystallographic plane of (100).

23. The semiconductor light-emitting device according to claim 16 or claim 17, wherein the off-angle is 30 degree or less.

24. The semiconductor light-emitting device according to claim 16 or claim 17, wherein a direction of the off-angle is a direction at an angle of −

30°

to 30°

from a direction perpendicular to a longitudinal direction of the stripe region.

25. The semiconductor light-emitting device according to claim 16 or claim 17, wherein a longitudinal direction of the stripe region is a direction at an angle of −

30°

to 30°

, and the off-angle direction is a direction at an angle of −

30°

to 30°

from a [0-11] direction.

17. A semiconductor light-emitting device comprising a substrate having a surface having an off-angle of 0.5°

to 30°

to a crystallographic plane of (100) or (111), the substrate having thereon;

compound semiconductor layers including an active layer, formed on said surface having said off-angle;

a protective film formed on the compound semiconductor layers and having an opening at the region corresponding to a stripe region to which a current is injected; and

a ridge-shaped compound semiconductor layer formed to cover the opening and a portion of a top surface of the protective film, wherein a side wall of the ridge-shaped compound semiconductor layer has a forward mesa shape.